| 1 | RQ | Swisswings AG | ICAO: RQX, Callsign: Swisswings, Ceased Operations on 08 April 2002. Name changed from Air Engiadina / Operated as KLM Alps. ICAO Callsign changed from Engiadina | CH | AVCODES |
| 2 | RQ | Air Engiadina | ICAO: RQX, Callsign: Engiadina, Name changed to Swisswings Airlines on 01 April 2001. Operates as KLM Alps | CH | AVCODES |
| 3 | RQ | Swisswings Airlines | ICAO: RQX, Callsign: Engiadina, ICAO Callsign changed to Swisswings. Name changed from Air Engiadina / Operated as KLM Alps | CH | AVCODES |
| 4 | RQ | International Synthetic Rubber Co. Ltd. | | GB | AVCODES |
| 5 | RQ | Arab Wing Nigeria Ltd. | Callsign: Romeo Quebec, | WAN | AVCODES |
| 6 | RQ | Kam Air | ICAO: KMF, Callsign: Kamgar, IATA Prefix: 384, | AFG | AVCODES |
| 7 | RQA | Royale Airlines International | Callsign: Royale, Ceased operations. | EAK | AVCODES |
| 8 | RQAX | RailQuest America, Inc. | 7/2005 (not listed) | | NAKINA |
| 9 | RQAX | RAILQUEST AMERICA, INC. | | | PWRC |
| 10 | RQAX | RailQuest America | | | RSRV |
| 11 | RQBI | ROAD QUEST BROKERAGE INC | | | SCAC4 |
| 12 | RQCT | R C T INC | | | SCAC4 |
| 13 | RQDL | RANDY QUICK DELIVERY | | | SCAC4 |
| 14 | RQDQ | RITE QUIK DELIVERY CO | | | SCAC3 |
| 15 | RQDQ | RAINBOW IRRIGATION AND EQUIPMENT IN | | | SCAC4 |
| 16 | RQEC | ROBO EXPRESS COMPANY | | | SCAC3 |
| 17 | RQEN | RENA NAVIGATION COMPANY LIMITED | | | SCAC3 |
| 18 | RQLI | REDLINE LOGISTICS INC | | | SCAC4 |
| 19 | RQLN | RUDISILL LOGISTICS INC | | | SCAC4 |
| 20 | RQLS | RAQUETTE LAKE SUPPLY CO INC | | | SCAC4 |
| 21 | RQMQ | REYES MANRIQUEZ, JULIA | | | SCAC4 |
| 22 | RQPM | R P M HARBOR SERVICES INC | | | SCAC4 |
| 23 | RQPR | REMOLQUES DE PUERTO RICO INC | | | SCAC3 |
| 24 | RQPR | REMOLQUES DE PUERTO RICO INC | | | SCAC4 |
| 25 | RQPT | RPM TRUCKLOAD INC | | | SCAC4 |
| 26 | RQSI | RTD QUALITY SERVICES INC | | | SCAC4 |
| 27 | RQSL | RELIABLE LOGISTICS SOLUTIONS LLC | | | SCAC4 |
| 28 | RQT | Airquest Aviation, LP | Callsign: Air Quest, | USA | AVCODES |
| 29 | RQTC | ROYAL TANKERS CORPORATION | | | SCAC3 |
| 30 | RQTG | R Q TRUCKING | | | SCAC4 |
| 31 | RQTH | ROMQUEST TECHNOLOGIES | | | SCAC4 |
| 32 | RQUD | RUDER BOSKOVIC SHIPPING COMPANY LTD | | | SCAC3 |
| 33 | RQWD | ROCQUEMORE, WAYNE D | | | SCAC3 |
| 34 | RQX | Swisswings AG | IATA: RQ, Callsign: Swisswings, Ceased Operations on 08 April 2002. Name changed from Air Engiadina / Operated as KLM Alps. ICAO Callsign changed from Engiadina | CH | AVCODES |
| 35 | RQX | Air Engiadina | IATA: RQ, Callsign: Engiadina, Name changed to Swisswings Airlines on 01 April 2001. Operates as KLM Alps | CH | AVCODES |
| 36 | RQX | Swisswings Airlines | IATA: RQ, Callsign: Engiadina, ICAO Callsign changed to Swisswings. Name changed from Air Engiadina / Operated as KLM Alps | CH | AVCODES |
| 37 | RQZF | RODRIQUEZ, FRANK J TRUCKING | | | SCAC3 |
